Measuring and regulating valve

ABSTRACT

Measuring and regulating valve assembly which includes a butterfly valve and a measuring flange, the measuring flange being situated upstream of the butterfly valve, the distance between the valve and the measuring flange being at least 0.6× the nominal passageway diameter, the assembly including a control box that has an adjustable stop that may contact a cam of a sleeve connected to an operating means whereby the maximum opening angle of the butterfly valve can be restricted in a reproducible manner, the sleeve being connected to the valve shaft.

The invention refers to a measuring and regulating valve especiallyintended for use in the heating system of a large building, providedwith a measuring flange with two connections for pressure gauges, saidmeasuring flange being situated upstreams of the actual stop valve whichmay be moved into open and closed positions as well into intermediatepositions with the aid of an operating means.

Well-known measuring and regulating valves of this type are usuallyprovided with a plug of which the axis forms an angle of about 60° withthe flow direction and are therefore quite long, for example 370 mm fora passageway of 100 mm. Then the plug is turned from the open to theclosed position and vice versa via a spindle and a knob. Setting such asystem involves balancing all resistances in the various lines, so thatthe minimally required flow rate is attained in every line.

In larger buildings there are often main lines that may each haveseveral side lines. In this case regulation takes place step-by-step,i.e. first the side lines, then the main lines and then the total flowby means of the pump.

Measuring and regulating units based on a butterfly valve are taken lessseriously than other, supposed better regulating principles such as plugvalves. The combination of measuring flange with butterfly valve isconsidered to produce poor measuring and regulating characteristics,i.e. low measuring accuracy, a small range of regulation and impreciseto meter owing to the nature of the butterfly valve that has anasymmetric build-up of pressure in the case of partly open positionsand, as a result of the short construction length, is placed too closeto the measuring flange to enable precise measurements to be taken atsaid measuring flange.

Nevertheless, the known measuring and regulating valves have demeritsthat could be eliminated more or less easily if a butterfly valve wereto be used anyhow. The main demerits are that the known valves requirehighly accurate handling in order to maintain the correct regulationset-up, that all the information concerning the setting must be read offfrom charts and that regulation can really only take place efficientlywhen two people are involved.

Surprisingly, it has turned out that a butterfly valve used for thepurpose described above can still produce very good results if thedistance between the valve and the measuring flange is minimally 0.6×the nominal passage-way and that, on said valve, a control box isarranged that comprises an adjustable stop that may come into contactwith a cam on a sleeve of the operating means so as to restrict themaximum opening angle of the butterfly valve in an accuratelyreproducible manner, said sleeve being provided on the valve shaft andhaving an indicator.

With a nominal passage-way of 100 mm the intended distance thereforeamounts to 60 mm, which results in an external length of about 120 mm.This is about 250 mm less than with the comparable measuring andregulating valve of the plug type.

The maximum opening angle of the butterfly valve is preferablyadjustable in the area between approx. 75° and 20°, the position of 0°ranking as closed position, in which area the invented measuring andregulating valve shows excellent linear regulating characteristics ascompared to well-known measuring and regulating valves of the plug type.

In the case of butterfly valves it is quite common for its angularposition to be detectable from the outside. Naturally, the inventedmeasuring and regulating valve also requires external visibility of theset position of the stop. One possibility to set the stop consists ofthe measures that the stop is provided with a horizontal threaded boreand that a screw, positioned in said threaded bore, is supported, inopposite side walls of a cap of the control box, in order to allow thestop to move recti-linearly through a groove in the bottom of thecontrol box while the maximum opening angle is being set. Externaldetection of the position of the stop can be obtained by the measuresthat the stop, at the side facing the valve shaft, is provided with arecess for a pin of a bounding plate that is mounted beneath the cap ofthe control box for pivotting around a bounding plate shaft, said shaftbeing aligned with the shaft of the butterfly valve.

With such a design it is practical for the indicator to be provided onthe sleeve of the operating means at such a height that said indicatormay move within a space of the cap of the control box, wherein saidspace is restricted downwardly by the top surface of a scale divisionthat is provided on a partition that guides the stop at its bottom sideand wherein said space is restricted upwardly by the bottom surface ofthe bounding plate.

At the side facing away from the indicator, the sleeve of the operatingmeans can merge into a circle-segment-shaped plate with acircle-segment-shaped groove through which a locking screw extends thathas been placed through a hole in the control box cap and has beenscrewed into the bottom of said control box.

In order to avoid the use of loose charts, nummerical data regarding thevalve and the measuring flange are given on the cap of the control box.

The invention will be further elucidated below with reference to thedrawings, in which, by way of example, an embodiment of a deviceaccording to the invention is shown. In the drawings:

FIG. 1 shows a perspective view of the measuring and regulating valve;

FIG. 2 shows a partly axially transected longitudinal view of FIG. 1;

FIG. 3 shows a rear view of FIG. 1, showing a cross-section beneath thecentral axis at the position of the measuring flange;

FIG. 4 shows, on a larger scale, a cross-section of the control boxaccording to line IV--IV of FIG. 2, and

FIG. 5 shows an example of the charts on the control box.

The device shown in FIG. 1 mainly consists of a butterfly valve casing1, a measuring flange casing 2 positioned upstreams of the butterflyvalve casing 1, a control box 3 located above the butterfly valve casing1, and an operating means 4 positioned in such a way that the butterflyvalve 5 is closed, which is called the 0°-position of said valve.

The nominal passage-way of a measuring and regulating valve is definedas a diameter of a certain order of size in which there can be someconicity, yet of course without any steps. The distance that is of anyrelevance to the invention is the minimal distance of 0.6× the nominalpassage-way, represented in FIG. 2 with A.

The butterfly valve casing 1 and the measuring flange casing 2 are bothprovided with four ears 6, so that they may be attached to each otherwith the aid of screws 7 and nuts 8. In the ears 6 of the butterflyvalve casing 1 there are relatively large holes 9 to allow(non-depicted) connecting means to pass, such as anchors with the aid ofwhich the assembly of the butterfly valve casing 1 and the measuringflange casing 2 can be clamped between the pipe flanges 10, 11 (FIG. 2)of the heating system. FIG. 3 shows that there are eight anchors in all.The butterfly valve casing 1 as well as the measuring flange casing 2are internally provided with a rubber lining 12 and 13 respectively.

Between the pairs of ears 6--located on top and at the bottom--of thebutterfly valve casing 1 stubs 14 are provided in the usual manner, inwhich the shafts of the butterfly valve 5 may rotate. In the drawingsonly the upper butterfly valve 15 is visible in FIGS. 2 and 4. The upperstub 14 of the butterfly valve casing 1 is provided with a flange 16(FIGS. 2 and 3) to which the control box 3 is attached by means of screwconnections 17.

In the lining 13 of the measuring flange casing 2 a ring 18 is providedthat is attached to a high pressure nipple 19 and a low pressure nipple20 in the usual way. By means of small hoses these nipples 19 and 20 areconnected to pressure gauge connections 22 on a kinked supporting plate23 arranged beneath the flange 15 of the stub 14 of the butterfly valvecasing 1. If no pressure difference gauge is present, as in the casedescribed above, the connections 22 are sealed off by means of plugs 24.

The control box 3, which is of special importance to this invention,consists of a bottom 25 in which a straight groove 53 is provided toguide a stop 26, and a cap 28, provided with a reading slit, with a rearwall 29, two side walls 30 and 31 and a front wall 32. The side wall 30and the front wall 32 leave a slit free in order to allow the operatingmeans 4 to move back and forth at an angle of 75° (or 90° if the stopwere to be removed). From the rear wall 29 a partition 33 projects in aninward direction from the control box 3, said partition guiding the stop26 on its bottom side and having a round scale division 34 from 0° to90° provided on its upper side.

The stop 26 is provided with a horizontal threaded bore 35 for a screw36 that is rotatably supported in the side walls 30 and 31 of thecontrol box 3 but is axially confined nevertheless. At an end that isaccessible from the outside, the screw 36 is provided with a socket hole37, so that the screw 36 can be turned with a (nondepicted) socket keyin order to displace the stop 26 through the groove 53 in the bottom 25of the control box 3.

The length of the groove 53 is such that the stop 26, at an openingangle of about 20°, is prevented from being moved further before thethreaded bore 35 becomes wedged against the threaded part of the screw36. It is therefore impossible to close the butterfly valve 5 completelywith the aid of the stop 26. The regulating range, with its boundariesbetween about 75° and 20°, is larger and especially linearly better thanis the case with valves of the usual type of plug.

At the side facing the butterfly valve shaft 15, the stop 26 is providedwith a recess 38 for a pin 39 of a bounding plate 40 that is arrangedbeneath the cap 28 of the control box 3 for pivoting around a verticalaxis 41. In view of the fact that said bounding plate 40 lies above theplane of cross-section in FIG. 4, it has been drawn there withchain-dotted lines. The vertical or bounding plate shaft 41 is alignedwith the butterfly valve shaft 15. Therefore, when the stop 26 is movedrecti-linearly, the bounding plate 40 is taken along and it then coversa more or less large angle area that borders on the maximum openposition of 70°. Then the butterfly valve 5 cannot reach said area, aswill be described below, and the position of the bounding plate 40 alsoclearly shows which area is meant; all the more if the bounding plate ispainted in a striking colour, red for example.

In the depicted embodiment the control means 4 consists of a handle 42that looks like the handlebars of a bicycle, said handle being connectedwith a sleeve 43 that is connected with the butterfly valve shaft 15through a hole in the bottom 25 of the control box 3. FIG. 4 shows thatthis connection consists of a so-called double D-profile. The sleeve 43comprises a cam 44 (FIG. 4) that abuts against the stop 26 when thevalve 5 is closed. At a height that, in FIG. 2, lies between the scaledivision 34 and the bounding plate 40, an indicator 45 projects from thesleeve 43. This has been indicated too in FIG. 4, by means ofchain-dotted lines as it lies above the plane of cross-section. It goeswithout saying, that the mutual positions of the cam 44 and theindicator 45 have been chosen in such a way that the indicator cannotcome into the area of the scale division 34 covered by the boundingplate 40.

The bottom 25 and the cap 28 of the control box 3 are connected to eachother by means of three socket bolts 46.

At the side facing away from the indicator 45, the sleeve 43 is providedwith a circle-segment shaped plate 45 that has an also circlesegment-shaped groove through which a lock screw 50 can move that hasbeen inserted through a hole 49 in the cap 28 and has been screwed intothe bottom 25. The circle-segment shaped groove 48 determines both theclosed or 0°-position as well as the fully open or 90°-position of thebutterfly valve 5, unless the latter position is restricted by the stop26. By tightening the lock screw 50 with the said of a knob 51, theoperating means 4 may be secured in a certain position.

As depicted in FIG. 5, on the cap 28 of the control box 3 charts 52 areprovided for a duct with a passageway of 100 mm. It is remarked that"valve" stand for valve and "orifice" stands for measuring flange.Furthermore

α=opening angle

ζ=resistance factor

φ=quantity of liquid in liters per second

Δρ=pressure difference factor in kPa.

It is therefore not necessary to have any graph at hand. In FIG. 5, inthe area beyond 70°, no numbers can be read to show that at least thearea beyond 70°-75° is covered by the bounding plate 40.

The invented measuring and regulating valve can be operated as follows:

if a heating system consists of several lines that must be measured andregulated individually, the amount of liquid needed per line with regardto the totally required heating capacity is already determined duringthe design phase, as well as the amount of liquid needed per line, withregard to resistances and loss of heat in ducts, valves, bends, liftheads and such on the one hand and the valve position that has to be seton the other hand. When the system has been fully installed, theregulation procedure is as follows:

The measuring and regulating valves are set at a position--calculatedand varying per strand--by turning the stop 26 into the desired positionwith the aid of the screw 36 with socket hole 37, and by fixing thebutterfly valve 5 against said stop by means of knob 51;

The pressure difference gauge is connected and the difference inpressure in read and compared to the desired Q-value of the chart 52 onthe control box 3. If adjustment is necessary, the knob 51 is turnedloose and the screw 36 is turned slowly in the desired direction untilthe difference in pressure on the pressure gauge corresponds to thecalculated Q.

When this precise regulating procedure has been concluded, the valve isagain secured by means of the knob 51;

Finally the other measuring and regulating valves of the remaining linesare set in the same way.

Other embodiments than the ones depicted in the drawing fall within thescope of the claims, in particular embodiments for use in processengineering.

I claim:
 1. A measuring and regulating valve assembly, comprising:a stopvalve (5) having a nominal passageway and moveable into open (90°),closed (0°) and intermediate positions with the aid of an operatingmeans (14) for rotating a valve shaft (15); a measuring flange withconnections for receiving a means for measuring a pressure differentialacross said flange, said measuring flange disposed upstream of said stopvalve; and a control box (3) with an adjustable stop (26) for limitingthe opening rotation of said operating means to restrict the maximumopening angle of said stop valve in an accurately reproducible manner,to any desired angle less than 90° said adjustable stop moveablerecti-linearly through a plane substantially perpendicular to the axisof said valve shaft while the maximum opening angle is being set. 2.Valve assembly according to claim 1, characterized in that the maximumopening angle of said stop valve (5) is adjustable between approx. 75°and 20°, the position of 0° ranking as the closed position.
 3. Valveassembly according to claim 1 characterized in that the angularpositions of said stop valve (5) and the stop (26) on the control box(3) are visually detectable.
 4. The valve assembly of claim 1 furthercomprising a rotatable screw (30) in said control box along which saidstop is movable in said plane.
 5. The valve assembly of claim 4 furthercomprising a groove (53) in said control box through which said stop ismovable along said screw.
 6. The valve assembly of claim 5 wherein saidcontrol box further comprises a threaded bore (35) through which saidscrew passes, and a cap (28) having opposite side walls (30,31) in whichsaid screw is supported and wherein said groove is disposed in thebottom (25) of said control box.
 7. Valve assembly according to claim 6characterized in that numerical data (52) regarding the valve and themeasuring flange are given on the control box (28).
 8. The valveassembly of claim 6 further comprising an indicator (45) for visuallydetecting the rotational position of said valve shaft and thus thecurrent angular position of said stop valve.
 9. Valve assembly accordingto claim 8, characterized in that the stop (26), at the side facing saidvalve shaft (15), is provided with a recess (38) for a pin (39) of abounding plate (40) that is mounted beneath the cap (28) of the controlbox (3) for pivoting around a bounding plate shaft, aligned with theshaft (15) of the stop valve.
 10. Valve assembly according to claim 9,characterized in that the indicator (45) is provided on the operatingmeans (4) at such a height that said indicator may move in a space ofthe cap (28) of the control box (3), wherein said space is restricteddownwardly by the top surface of a scale division (34) that is providedon a partition (33) that guides the stop (26) at its bottom side andwherein said space is restricted upwardly by the bottom surface of thebounding plate (40).
 11. Valve assembly according to claim 8,characterized in that a sleeve (43) of the operating means (4), at theside facing away from the indicator (45), merges into acircle-segment-shaped plate (47) with a circle-segment-shaped groove(48) through which a locking screw (50) extends that has been placedthrough a hold (49) in the control box cap (28) and has been screwedinto the bottom (25) of said control box.
 12. Valve assembly accordingto claim 8, wherein the maximum opening angle setting provided by theadjustable stop (26) is visually detectable on a scale division (34)functionally positioned with respect to the indicator (45).
 13. Thevalve assembly of claim 1 wherein the distance between said valve stopand said measuring flange is at least 0.6× said nominal passageway. 14.The valve assembly of claim 1 wherein said stop valve is a butterflyvalve.
 15. A method of adjusting the maximum opening angle of ameasuring and regulating valve assembly comprising a stop valve (5)having a nominal passageway and moveable into open (90°), closed (0°)and intermediate positions with the aid of an operating means (14) forrotating a valve shaft (15), and a measuring flange with connections forreceiving a means for measuring a pressure differential across saidflange, said measuring flange disposed upstream of said stop valve, themethod comprising:providing a rotating valve (15) as the stop valve;providing a control box (3) with an adjustable stop (26) for limitingthe opening rotation of said operating means to restrict the maximumopening angle of said stop valve in an accurately reproducible manner toany desired angle less than 90°; and moving said adjustable stoprecti-linearly through a plane substantially perpendicular to the axisof said valve shaft from an initial position adjust to the desiredmaximum opening angle.
 16. The method as defined in claim 15, furthercomprising:providing a visual indication of both the maximum openingangle of the butterfly valve and the current angular position of thebutterfly valve.
 17. The method as defined in claim 15, furthercomprising:initially setting the adjustable stop such that the maximumopening angle is at an initial selected position; while passing fluidthrough said measuring flange of said valve assembly, detecting thepressure differential across said measuring flange; and adjusting theinitial setting of said adjustable stop in response to the differentialpressure to obtain the desired maximum opening angle of said rotatingvalve.
 18. The method as defined in claim 17, furthercomprising:providing a visual indication of the open, closed andintermediate positions of said rotating valve.
 19. The method as definedin claim 17, further comprising:carrying said adjustable stop on a screw(30) mounted in a groove (53) in said control box; and rotating saidscrew to recti-linearly move said adjustable stop through said plane.20. The method as defined in claim 17, further comprising providing abutterfly valve as the stop valve.
 21. The method as defined in claim17, further comprising limiting the maximum opening angle of said stopvalve between approximately 75° and 20°.